Incredible giant virus linked to life’s origins discovered

Unlike medusavirus, which replicates inside an intact host nucleus, ushikuvirus ruptures the nuclear membrane to produce new particles. This behaviour bridges the gap between viruses that use intact nuclei and those, like pandoraviruses, that destroy them. These variations likely arose as adaptations to different amoeba hosts.

The research team included TUS master’s students Jiwan Bae and Narumi Hantori, alongside Dr Raymond Burton-Smith and Professor Kazuyoshi Murata from the National Institute of Natural Sciences. Using advanced 3D cryo-electron microscopy, they revealed the virus’s intricate spiked surface in stunning detail.

Reflecting on the evolutionary significance, Takemura says: “The discovery of a new Mamonoviridae-related virus, ‘ushikuvirus,’ which has a different host, is expected to increase knowledge and stimulate discussion regarding the evolution and phylogeny of the Mamonoviridae family. As a result, it is believed that we will be able to get closer to the mysteries of the evolution of eukaryotic organisms and the mysteries of giant viruses.”

The implications reach beyond evolutionary biology. Certain amoebae cause serious human infections, including blinding keratitis and fatal encephalitis. Understanding how ushikuvirus efficiently destroys its host could inspire new strategies to prevent or treat such parasitic infections.

Funded by Japanese grants, the study reinforces Tokyo University of Science’s reputation as a premier research institution. As more giant viruses emerge from the environment, ushikuvirus serves as a reminder that ancient microbial interactions continue to shape the map of life today.

Article source: https://www.express.co.uk/news/science/2154720/incredible-giant-virus-linked-life-japan-ushikuvirus